<template>
	<view class="content">
		<view class="navbar" :style="{position:headerPosition,top:headerTop}">
			<view class="nav-item" :class="{current: filterIndex === 0}" @click="tabClick(0)">
				综合排序
			</view>
			<view class="nav-item" :class="{current: filterIndex === 1}" @click="tabClick(1)">
				销量优先
			</view>
			<view class="nav-item" :class="{current: filterIndex === 2}" @click="tabClick(2)">
				<text>价格</text>
				<view class="p-box">
					<text :class="{active: this.shopInfo.priceOrder === 1 && filterIndex === 2}" class="yticon icon-shang"></text>
					<text :class="{active: this.shopInfo.priceOrder === 2 && filterIndex === 2}" class="yticon icon-shang xia"></text>
				</view>
			</view>
			<!-- 右上角分类页面 -->
			<text class="cate-item yticon icon-fenlei1" @click="toggleCateMask('show')"></text>
		</view>
		<view class="goods-list">
			<view 
				v-for="(item,index) in goodsList" :key="index"
				class="goods-item"
				@click="navToDetailPage(item)"
			>
				<view class="image-wrapper">
					<image :src="item.picurl" mode="aspectFill"></image>
				</view>
				<text class="title clamp">{{item.commodityid}}</text>
				<view class="price-box">
					<!-- 折扣价有值就显示折扣后价格，没值说明没折扣，则显示原价 -->
					<text class="price">{{item.discountAfter || item.commoditymoney}}</text>
					<text>已售 {{item.salesvolume}}</text>
				</view>
			</view>
		</view>
		<uni-load-more :status="loadingType"></uni-load-more>
		
		<!-- 分类页面 -->
		<view class="cate-mask" :class="cateMaskState===0 ? 'none' : cateMaskState===1 ? 'show' : ''" @click="toggleCateMask">
			<view class="cate-content" @click.stop.prevent="stopPrevent" @touchmove.stop.prevent="stopPrevent">
				<scroll-view scroll-y class="cate-list">
					<view v-for="item in cateList" :key="item.id">
						<view class="cate-item b-b two">{{item.name}}</view>
						<view 
							v-for="tItem in item.children" :key="tItem.id" 
							class="cate-item b-b" 
							:class="{active: tItem.id == cateId}"
							@click="changeCate(tItem)">
							{{tItem.name}}
						</view>
					</view>
				</scroll-view>
			</view>
		</view>
		
	</view>
</template>

<script>
	import uniLoadMore from '@/components/uni-load-more/uni-load-more.vue';
	export default {
		components: {
			uniLoadMore	
		},
		data() {
			return {
				cateMaskState: 0, //分类面板展开状态
				headerPosition:"fixed",
				headerTop:"0px",
				loadingType: 'more', //加载更多状态
				filterIndex: 0, 
				cateList: [],
				goodsList: [],
				shopInfo:{
					categoryId: 0, //已选三级分类id
					orderBy:undefined,  //排序 0综合 1销量 2价格
					priceOrder: 0, //1 价格从低到高 2价格从高到低
				},
				cateId:0
			};
		},
		//页面加载事件
		onLoad(options){
			//给二级分类页面添加默认点击样式
			this.cateId = options.sid;
			// #ifdef H5
			this.headerTop = document.getElementsByTagName('uni-page-head')[0].offsetHeight+'px';
			// #endif
			//接收三级分类id
			this.shopInfo.categoryId = options.sid;
			this.loadCateList(options.fid);
			this.loadData("refresh",options.sid);
		},
		//下拉刷新函数
		onPullDownRefresh(){
			this.loadData("refresh");
		},
		//加载更多
		onReachBottom(){
			// this.loadData();
		},
		methods: {
			//加载商品 ，带下拉刷新和上滑加载
			async loadData(type='refresh') {	
				//清空商品列表，刷新
				this.goodsList = [];
				//默认查询商品 综合
				// if(type === "add"){
				// 	//综合排序
				// 	this.goodsList = (await this.$api.reqGet({
				// 		url:"/ygCommodity/cateAllTwo?categoryId="+this.shopInfo.categoryId
				// 	})).data;
				// 	console.log(this.goodsList)
				// } 
				//访问后端接口 综合 销量 价格 排序
				if(type === "refresh"){
					this.goodsList = (await this.$api.reqPost({
						url:"/ygCommodity/orderBy",
						data:this.shopInfo
					})).data;
				}
				//模拟 取消 "正在加载"；取消 "页面下拉
				setTimeout(()=>{
					//取消加载
					uni.hideLoading();
					//取消下拉标识
					uni.stopPullDownRefresh();
				}, 250);
				//判断是否还有下一页，有是more  没有是nomore(测试数据判断大于20就没有了)
				this.loadingType  = this.goodsList.length > 20 ? 'nomore' : 'more';
			},
			
			
			//点击菜单 进行筛选按钮
			async tabClick(index){
				//如果一致代表重复点击，则直接return
				if(this.filterIndex === index && index !== 2){
					return;
				}else if(index === 0){
					this.loadData();
				}else if(index === 2){
					//判断用户已经点击了一次价格排序 低到高，再次点击就是高到低
					this.shopInfo.priceOrder = this.shopInfo.priceOrder === 1 ? 2 : 1;
				}else{
					this.shopInfo.priceOrder = 0;
				}
				//接收用户点击下标
				this.shopInfo.orderBy = index;
				//将下标赋值给带点击样式
				this.filterIndex = index;
				//正在加载
				uni.showLoading({
					title: '正在加载'
				})
				this.loadData("refresh");
			},
			
			//显示隐藏分类面板
			toggleCateMask(type){
				let timer = type === 'show' ? 10 : 300;
				let	state = type === 'show' ? 1 : 0;
				this.cateMaskState = 2;
				setTimeout(()=>{
					this.cateMaskState = state;
				}, timer)
			},
			//分类点击
			changeCate(item){
				this.shopInfo.categoryId = item.id;
				this.toggleCateMask();
				this.cateId = item.id;
				this.loadData("refresh");
				uni.showLoading({
					title: '正在加载'
				})
			},
			//访问后台接口获取二三级分类
			async loadCateList(fid){
				this.cateList = (await this.$api.reqGet({
					url:"/ygCategory/categoryById?fid="+fid
				})).data;
			},
			
			//跳转商品详情页面
			navToDetailPage(item){
				//测试数据没有写id，用title代替
				let commodityid = item.commodityid;
				let id = item.id;
				uni.navigateTo({
					url: `/pages/product/product?id=${id}&commodityid=${commodityid}`
				})
			},
			
			//兼容iOS端下拉时顶部漂移
			onPageScroll(e){
				if(e.scrollTop>=0){
					this.headerPosition = "fixed";
				}else{
					this.headerPosition = "absolute";
				}
			},
			
			stopPrevent(){}
		},
	}
</script>

<style lang="scss">
	page, .content{
		background: $page-color-base;
	}
	.content{
		padding-top: 96upx;
	}

	.navbar{
		position: fixed;
		left: 0;
		top: var(--window-top);
		display: flex;
		width: 100%;
		height: 80upx;
		background: #fff;
		box-shadow: 0 2upx 10upx rgba(0,0,0,.06);
		z-index: 10;
		.nav-item{
			flex: 1;
			display: flex;
			justify-content: center;
			align-items: center;
			height: 100%;
			font-size: 30upx;
			color: $font-color-dark;
			position: relative;
			&.current{
				color: $base-color;
				&:after{
					content: '';
					position: absolute;
					left: 50%;
					bottom: 0;
					transform: translateX(-50%);
					width: 120upx;
					height: 0;
					border-bottom: 4upx solid $base-color;
				}
			}
		}
		.p-box{
			display: flex;
			flex-direction: column;
			.yticon{
				display: flex;
				align-items: center;
				justify-content: center;
				width: 30upx;
				height: 14upx;
				line-height: 1;
				margin-left: 4upx;
				font-size: 26upx;
				color: #888;
				&.active{
					color: $base-color;
				}
			}
			.xia{
				transform: scaleY(-1);
			}
		}
		.cate-item{
			display: flex;
			justify-content: center;
			align-items: center;
			height: 100%;
			width: 80upx;
			position: relative;
			font-size: 44upx;
			&:after{
				content: '';
				position: absolute;
				left: 0;
				top: 50%;
				transform: translateY(-50%);
				border-left: 1px solid #ddd;
				width: 0;
				height: 36upx;
			}
		}
	}

	/* 分类 */
	.cate-mask{
		position: fixed;
		left: 0;
		top: var(--window-top);
		bottom: 0;
		width: 100%;
		background: rgba(0,0,0,0);
		z-index: 95;
		transition: .3s;
		
		.cate-content{
			width: 630upx;
			height: 100%;
			background: #fff;
			float:right;
			transform: translateX(100%);
			transition: .3s;
		}
		&.none{
			display: none;
		}
		&.show{
			background: rgba(0,0,0,.4);
			
			.cate-content{
				transform: translateX(0);
			}
		}
	}
	.cate-list{
		display: flex;
		flex-direction: column;
		height: 100%;
		.cate-item{
			display: flex;
			align-items: center;
			height: 90upx;
			padding-left: 30upx;
 			font-size: 28upx;
			color: #555;
			position: relative;
		}
		.two{
			height: 64upx;
			color: #303133;
			font-size: 30upx;
			background: #f8f8f8;
		}
		.active{
			color: $base-color;
		}
	}

	/* 商品列表 */
	.goods-list{
		display:flex;
		flex-wrap:wrap;
		padding: 0 30upx;
		background: #fff;
		.goods-item{
			display:flex;
			flex-direction: column;
			width: 48%;
			padding-bottom: 40upx;
			&:nth-child(2n+1){
				margin-right: 4%;
			}
		}
		.image-wrapper{
			width: 100%;
			height: 330upx;
			border-radius: 3px;
			overflow: hidden;
			image{
				width: 100%;
				height: 100%;
				opacity: 1;
			}
		}
		.title{
			font-size: $font-lg;
			color: $font-color-dark;
			line-height: 80upx;
		}
		.price-box{
			display: flex;
			align-items: center;
			justify-content: space-between;
			padding-right: 10upx;
			font-size: 24upx;
			color: $font-color-light;
		}
		.price{
			font-size: $font-lg;
			color: $uni-color-primary;
			line-height: 1;
			&:before{
				content: '￥';
				font-size: 26upx;
			}
		}
	}
	

</style>
